Dyestuffs and process of making same.



UNITED STATES PATENT OFFICE.

HERMANN WAGNER AND JOSEF ERBER, OF H ClCHST-ON-THE-MAIN, GERMANY,

ASSIGNORS T0 FARIBWERKE VORM. MEISTER LUCIUS & BRfiNING, 0F HfiCHST- ON-THE-MAIN, GERMANY, A CORPORATIONOF GERMANY.

No Drawing.

Specification of Letters Patent.

. Patented Oct. 22, 1912.

Application filed February 23, 1912. Serial No. 679,374.

To all whom it may concern:

Be it known that we, HERMANNWA NER, Ph. D., chemist, and Josnr ERBER, Ph. D., chemist, citizens of the Empire of Germany, residing at Hochst-on-the-Main, Germany, have invented certain new and useful Improvements in New Dyestuffs andProcesses of Making Same, of'which the following is a specification.

This invention relates to the manufacture of dyestuffs by coupling the tetrazo compound of the 2:2 -benzidindisulfonic acid with 1- (2-chlorphenyl) -3-methyl-5-pyrazolone, or with 1 (2 :5 dichlorphenyl) 3- methyl 5-pyrazolone.

The new dyestufis have the general constitutional formula:

S0311 scan R-N=-N %/N-NR wherein R stands for a halogenated pyrazolone. The alkali salts of these dyestufis form, when dry, yellow powders,

remarkable for their pure yellow tint tending toward green, and are very valuable for dyeing Wool as well as for the preparation of color lakes.

Theinvention is illustrated by the following examples y 1. The tetrazo compound obtained in the usual manner from 34.4 kilos of 2:2 -benzidindisulfonic acid is run into an aqueous solution of 41.7 kilos of l-'(2-chlorphenyl)- 3-methyl-5-pyrazolone in caustic soda lye and sodium carbonate. When the reaction is finished, the dyestufi' is separated in the usual manner. The coupling may also be effected in an acetic acid solution.

2. The tetrazo compound obtained from 34.4 kilos of 2:2 -benzidindisulfonic acid is run into an aqueous solution of 48.6 kilos of 1 (2 :5 dichlorphenyl) 3 -methyl-5-pyrazolone in caustic sodalye and sodium carbonate. When the reaction is finished, the dyestufi' is separated in the usual manner. The coupling may also be eifected in an acetic acid solution. This product has the readily soluble in water. The dyestuffs are formula:

it HN TO I SIO'H SfihH 0G omo G-N-N N=N-t=c-cm.

7\ In order to prepare the color lakes, the 1. As new products, the herein-described dyestufl is, for instance, precipitated 'in an dyestufis of the general -forn1'ula:- aqueous solution by barium chlorld upon a 03E S0311:

substratum such, for instance, as heavy spar or aluminium hydroxid. Thus color-lakes of pure yellow, bright tints are obtained.

Having now described our invention, What we claim, is-

wiherein 'R standsfo-r ahalogenated pyu'az- 6 5 olone, the alkalivsalts of which, when dry,

form yellow powders, readily soluble in eenew 3. The process of manufacturing yellow dyestufis, which consists in diazotizing benzidin-m-disulfonic acid and coupling it with a halogenated pyrazolone.

SOBH

l the alkali salts of which, when dry, form a In testimony whereof, we alfix our signayellow powder, readily soluble in water, dyetures in presence of two witnesses.

ing wool a pure yellow tint with a green HERMANN WAGNER.

hue, and being very suitable for the prepare J OSEF ERBER. tion of color lakes.

/ Milli Witnesses JEAN GRUND, CARL GRUND. 

